Recently, I found myself in a situation where I needed a Linux mount point of sufficient space for GoldenGate binaries / trail files. I’ve used the Oracle Database File System (DBFS) option in the past, although I never really was a big fan of it since its use creates additional database objects and in my opinion unnecessary additional database I/O as well as additional redo and rman activity. Based on this, I decided to explore the use of Oracle ASM Clustered File System (ACFS) for this use case. At first glance, it seemed to be much faster to set up and was available on all nodes by default, which would also allow GoldenGate to fail over to other nodes. In addition, ACFS does not require the database to be up so the filesystem can also be used for other purposes. If you are using this mount solely for GoldenGate, make sure you follow the best practices document which is updated periodically (Oracle GoldenGate Best Practice: NFS Mount options for use with GoldenGate (Doc ID 1232303.1))
*** Refer to the following steps at your own risk and always test for your use case prior to using in a production setting.
- Root user access
- Sufficient ASM Space
- Separate ASM Diskgroup (Optional)
- Latest Oracle Grid Infrastructure and Database Patchset
Verify that ACFS/ADVM modules are present in memory (on each node):
$ lsmod | grep oracle
If the modules are not present, the command will return something similar to:
oracleasm 53591 1
If the modules are present, the command will return something similar to:
oracleacfs 3308260 0
oracleadvm 508030 0
oracleoks 506741 2 oracleacfs,oracleadvm
oracleasm 53591 1
If the modules are not present or you would like to ensure that the latest version is loaded, run the following before proceeding (as the root user):
$ . oraenv ORACLE_SID = [CDBRAC1] ? +ASM The Oracle base remains unchanged with value /u01/app/oracle # $GRID_HOME/bin/acfsroot install
Reboot the node if the modules were already present and you are reloading them.
Start and enable the ACFS modules on each node:
On each node and as the root user:
# $GRID_HOME/bin/acfsload start ACFS-9391: Checking for existing ADVM/ACFS installation. ACFS-9392: Validating ADVM/ACFS installation files for operating system. ACFS-9393: Verifying ASM Administrator setup. ACFS-9308: Loading installed ADVM/ACFS drivers. ACFS-9327: Verifying ADVM/ACFS devices. ACFS-9156: Detecting control device '/dev/asm/.asm_ctl_spec'. ACFS-9156: Detecting control device '/dev/ofsctl'. ACFS-9322: completed
If running Grid Infrastructure, enable the driver modules in clusterware (only on one node as the root user):
# $GRID_HOME/bin/acfsroot enable ACFS-9376: Adding ADVM/ACFS drivers resource succeeded. CRS-2672: Attempting to start 'ora.drivers.acfs' on 'orcl-rac1' CRS-2676: Start of 'ora.drivers.acfs' on 'orcl-rac1' succeeded ACFS-9380: Starting ADVM/ACFS drivers resource succeeded. ACFS-9368: Adding ACFS registry resource succeeded. CRS-2672: Attempting to start 'ora.registry.acfs' on 'orcl-rac2' CRS-2672: Attempting to start 'ora.registry.acfs' on 'orcl-rac1' CRS-2676: Start of 'ora.registry.acfs' on 'orcl-rac2' succeeded CRS-2676: Start of 'ora.registry.acfs' on 'orcl-rac1' succeeded ACFS-9372: Starting ACFS registry resource succeeded.
Once installation is complete, and the mount is registered with clusterware, these modules will be loaded automatically.
If you like you can double check the driverstate by using the following executable:
usage: acfsdriverstate [-orahome ] [-s]
As oracle user, create an ASM volume for ACFS (run only on one node):
Source in the grid environment.
$ . oraenv ORACLE_SID = [CDBRAC1] ? +ASM The Oracle base remains unchanged with value /u01/app/oracle
Create the volume using the volcreate command.
You can use an existing disk group or create a separate one to house ACFS.
$ asmcmd ASMCMD> volcreate -G DATA -s 10G ACFSVOL1 ASMCMD> volinfo --all Diskgroup Name: DATA Volume Name: ACFSVOL1 Volume Device: /dev/asm/acfsvol1-370 State: ENABLED Size (MB): 1024 Resize Unit (MB): 64 Redundancy: UNPROT Stripe Columns: 8 Stripe Width (K): 1024 Usage: Mountpath:
As oracle user, create the filesystem on the volume which was just created:
$ /sbin/mkfs -t acfs /dev/asm/acfsvol1-370 mkfs.acfs: version = 188.8.131.52.0 mkfs.acfs: on-disk version = 39.0 mkfs.acfs: volume = /dev/asm/acfsvol1-370 mkfs.acfs: volume size = 1073741824 ( 1.00 GB ) mkfs.acfs: Format complete.
As root, create an empty directory which will house the file system:
# mkdir -p /acfsmounts/acfsvol1 # chown root:oinstall /acfsmounts # chmod 770 /acfsmounts # chown -R oracle:oinstall /acfsmounts/acfsvol1 # chmod 775 /acfsmounts/acfsvol1
As root, setup the file system to be auto mounted by clusterware:
In a RAC 11g environment, you use acfsutil (srvctl may be supported – was not tested and the “-u option” will allow the oracle user to administer the mount):
# . /usr/local/bin/oraenv ORACLE_SID = [CDBRAC1] ? +ASM The Oracle base remains unchanged with value /u01/app/oracle # /sbin/acfsutil registry -a /dev/asm/acfsvol1-370 /acfsmounts/acfsvol1 -t "ACFS General Purpose Mount" -u oracle
In a RAC 12c GI environment, register it with clusterware using the following commands (the “-u option” will allow the oracle user to administer the mount):
# .&amp;nbsp;/usr/local/bin/oraenv ORACLE_SID = [CDBRAC1] ? +ASM The Oracle base remains unchanged with value /u01/app/oracle # srvctl add volume -volume ACFSVOL1 -diskgroup DATA -device /dev/asm/acfsvol1-370 # srvctl add filesystem -device /dev/asm/acfsvol1-370 -path /acfsmounts/acfsvol1 -diskgroup DATA -user oracle -fstype ACFS -description "ACFS General Purpose Mount"
At this point the mount should be ready for read/write and will be automatically mounted by clusterware.
Administration of the ACFS mount:
If you need to resize the mount once created (since you granted control to the oracle user, this command can also be executed by the oracle user:
$ acfsutil size 25G /acfsmounts/acfsvol1 $ srvctl start filesystem -device /dev/asm/acfsvol1-370 $ srvctl stop filesystem -device /dev/asm/acfsvol1-370